Display panel

ABSTRACT

A display panel comprising a first substrate, a second substrate and a light shielding layer is provided. The first substrate comprises several display units arranged in a matrix and forming an image display region. The display units comprise m*n pixels arranged in a matrix. The second substrate is opposite to the first substrate. The light shielding layer located between the first substrate and the second substrate comprises several extending portions. The projection of one of the extending portions on the first substrate overlaps at least one of the pixels. Each pixel having the largest overlapping area with the extending portion is a first pixel, and other pixels are second pixels. In each display unit, there is at most one first pixel per column and per row. In the image display region, all of the pixels adjacent to the first pixel are second pixels.

This application claims the benefit of Taiwan application Serial No.103120001, filed Jun. 10, 2014, the subject matter of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates in general to a display panel, and moreparticularly to a flat display panel.

2. Description of the Related Art

The generally known display panel comprises a plurality of pixels. Thedisplay panel displays an image by mixing the colors and brightness ofthe pixels. Adjacent pixels are separate by a light shielding layerwhich increases the contrast between pixels and shields signal traces.

Normally, the light shielding layer is not one-sized. In some regions ofthe display panel, the light shielding layer is enlarged to shield partsof the structure such as spacers. The enlarged light shielding layershields the display region of adjacent pixels, hence decreasing theaperture ratio (AR) of adjacent pixels. That is, the pixels of thedisplay panel at least have two aperture ratios. However, when thepixels with lower aperture ratio are arranged in a repetitive manner,the image may look having strips to the viewer's naked eyes, the displayquality and visual quality of the panel will be affected.

SUMMARY OF THE INVENTION

The invention is directed to a display panel capable of improving visualquality without increasing the aperture ratio through special patterndesign of the light shielding layer.

According to one embodiment of the present invention, a display panel isprovided. The display panel comprises a first substrate, a secondsubstrate and a light shielding layer. The first substrate comprises aplurality of display units arranged in a matrix and forming an imagedisplay region. The display unit comprise m*n pixels arranged in an m*nmatrix, wherein m and n are positive integers m≧6, and n≧2. The secondsubstrate is opposite to the first substrate. The light shielding layeris located between the first substrate and the second substrate. Thelight shielding layer comprises a plurality of extending portions. Aprojection of one of the extending portions on the first substrateoverlaps at least two of the pixels. One of the two pixels having largeroverlapping area with the extending portions is a first pixel, and theother one is a second pixel. In each display unit, there is at most onefirst pixel per column and per row, and in the image display region, allof the pixels adjacent to the first pixel are second pixels.

According to another embodiment of the present invention, a displaypanel is provided. The display panel comprises a first substrate, asecond substrate and a light shielding layer. The first substratecomprises a plurality of display units arranged in a matrix and formingan image display region. The display units comprise m*n pixels arrangedin an m*n matrix. Each pixel has at least three sub-pixels, wherein mand n are positive integers, m≧2, and n≧2. The second substrate isopposite to the first substrate. The light shielding layer is locatedbetween the first substrate and the second substrate. The lightshielding layer comprises a plurality of extending portions. Aprojection of one of the extending portions on the first substrateoverlaps at least one of the pixels. The pixel overlapping theprojection of the extending portion is a first pixel. Other pixels notoverlapping the projection of the extending portion are second pixels.In each display unit, there is at most one first pixel per column andper row, and in the image display region, all of the pixels adjacent tothe first pixel are second pixels.

The above and other aspects of the invention will become betterunderstood with regard to the following detailed description of thepreferred but non-limiting embodiment (s). The following description ismade with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a planar diagram of a display panel according to an embodimentof the invention.

FIG. 2A is a partial enlarged diagram of the display panel of FIG. 1.

FIG. 2B is a cross-sectional diagram of the display panel of FIG. 2A.

FIG. 3 is a planar diagram of a display panel according to anotherembodiment of the invention.

FIG. 4 is a planar diagram of a display panel according to an alternateembodiment of the invention another.

FIG. 5 is a planar diagram of a display panel according to an embodimentof the invention.

FIG. 6 is a planar diagram of a display panel according to anotherembodiment of the invention.

FIG. 7 is a planar diagram of a display panel according to an alternateembodiment of the invention.

FIG. 8 is a planar diagram of a display panel according to anotheralternate embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

A number of embodiments are disclosed below with accompanying drawingsfor elaborating the invention. It should be noted that the drawings aresimplified so as to provide clear descriptions of the embodiments of theinvention, and the scales used in the drawings are not based on thescales of actual products. However, the embodiments of the invention arefor detailed descriptions only, not for limiting the scope of protectionof the invention.

Refer to FIG. 1 to FIG. 2B. FIG. 1 is a planar diagram of a displaypanel according to an embodiment of the invention. FIG. 2A is a partialenlarged diagram of two side-by-side display units 10 of the displaypanel of FIG. 1. FIG. 2B is a cross-sectional diagram of the displaypanel of FIG. 2A viewed along a cross-sectional line 2B-2B′. The displaypanel 1 comprises a first substrate 100, a second substrate 200 and alight shielding layer 300. The first substrate 100 comprises a pluralityof identical display units 10 arranged in a matrix and forming an imagedisplay region 11.

As indicated in FIG. 2A and FIG. 2B, the display unit 10 comprises m*npixels arranged in an m*n matrix 20, wherein m and n are positiveintegers m≧2, and n≧2, and each pixel 20 is composed of at least threesub-pixels corresponding to different colors. The second substrate 200is opposite to the first substrate 100. The light shielding layer 300 islocated between the first substrate 100 and the second substrate 200 anddisposed on one of the first substrate 100 and the second substrate 200.In the present embodiment, the light shielding layer 300 is realized bya black matrix (BM) and disposed on the second substrate 200. The lightshielding layer 300 comprises a plurality of extending portions 310. Theprojection of each extending portion 310 on the first substrate 100overlaps at least one pixel 20 (each extending portion 310 overlaps fourpixels 20 as indicated in FIG. 2A). In the present invention, the pixel20 having the largest overlapping area with the extending portion 310 isdefined as a first pixel 21, and other pixels 20 with smalleroverlapping area with the extending portion 310 or not overlapping theextending portion 310 are defined as second pixels 22. In each displayunit 10, there is at most one first pixel 21 per column and per row. Inthe entire image display region, all pixels adjacent to the first pixel21 are second pixels 22.

In the display panel 1 of the embodiment of the present invention, byadjusting the position of each extending portion 310 of the lightshielding layer 300, the first pixels 21 with lower aperture ratiooverlapped by the extending portion 310 can be distributed over theentire image display region and occupy a certain percentage. Since thefirst pixels 21 are not easily detected by naked eyes, the viewer willnot perceive image strips, and display quality can thus be improved.

FIG. 2A illustrates two display units 10 for exemplary purpose. Eachdisplay unit 10 comprises 12 pixels arranged in a 6*2 matrix 20 (6 rows,2 columns). It should be noted that each pixels 20 comprises threesub-pixels respectively designated by the three primary colors red (R),green (G), and blue (B). The light shielding layer 300 is disposed atthe interval between any adjacent two of the sub-pixels R, G and B, andextends along the X-axis direction and the Y-axis direction to form agrid shape. The light shielding layer 300 covers the trace and dividesthe display unit 10 into different color blocks. In the presentembodiment, each extending portion 310 of the light shielding layer 300is disposed at the junction between the four pixels 20, such that theprojection of the each extending portion 310 on the first substrate 100partially overlaps the four pixels 20. The overlapping area between thepixels 20 and each extending portion 310 does not display colors, henceaffecting the aperture ratio of the pixels 20. The projection of theextending portion 310 overlaps the four pixels 20 by differentoverlapping areas. The one of the four pixels 20 having the largestoverlapping area with the extending portion 310 is defined as a firstpixel 21, and the other three pixels 20 with smaller overlapping areaswith the extending portion 310 are defined as second pixels 22. In thepresent invention, each pixel 20 not overlapping with any extendingportions 310 is defined as a second pixel 22. That is, the apertureratio of the first pixel 21 is smaller than the aperture ratio of thesecond pixel 22. By adjusting the positions of the extending portions310 of the light shielding layer 300, the first pixels 21 with loweraperture ratio and occupying a certain percentage can be uniformlydistributed on the display unit.

As indicated in the display panel 1 of FIG. 2A, the light shieldinglayer 300 comprises a plurality of connecting portions 320. Theconnecting portions 320 connect the extending portions 310 and shieldthe traces such as scan lines or data lines of the display panel 1 toachieve light shielding effect. Each connecting portion 320 is disposedbetween any adjacent two of the sub-pixels R, G and B and connects theextending portions 310. The width of each connecting portion 320 on theY-axis direction is smaller than that in the Y-axis direction.

As indicated in the display panel 1 of FIG. 2A, the light shieldinglayer 300 further comprises a plurality of sub-extending portions 330.Like the extending portions 310, the sub-extending portions 330 aredisposed at the junctions between the sub-pixels R, G and B. Eachconnecting portion 320 connects two adjacent sub-extending portions 330,or connects one adjacent extending portion 310 and one adjacentsub-extending portion 330. In the Y-axis direction, the width of thesub-extending portion 330 is greater than the width of the connectingportion 320 but is smaller than the width of the extending portion 310.The projection of each sub-extending portion 330 on the first substrate100 also shields adjacent sub-pixels R, G and B, but the overlappingarea is smaller than the projection of each extending portion 310 on thefirst substrate 100. Thus, the pixels overlapped by the projection ofeach the sub-extending portion 330 are still defined as second pixels.In some embodiments, the light shielding layer 300 of the display panelcan be dispensed with the sub-extending portions 330 and can comprisesingle-sized extending portions 310 and connecting portions 320 insteadas indicated in FIG. 3.

As indicated in FIG. 2B, the display panel 1 further comprises a filterlayer 400 and a spacer 500. The filter layer 400 is located between thefirst substrate 100 and the second substrate 200 and can be disposed onone of the first substrate 100 and the second substrate 200. In thepresent example, the filter layer 400 is exemplarily disposed on thesecond substrate 200. The filter layer, such as a photo-resist, can makethe sub-pixels R, G and B display three different colors. The positionof the filter layer 400 corresponds to the sub-pixels R, G and B of FIG.2A. The spacer 500 is located between the first substrate 100 and thesecond substrate 200, and can be disposed on the first substrate 100 orthe second substrate 200. In the present example, the spacer 500 isexemplarily disposed on the second substrate 200. The spacer 500 fixesthe interval between the first substrate 100 and the second substrate200. To avoid the frame being affected by the spacer 500, the positionof the spacer 500 corresponds to the extending portion 310 or thesub-extending portion 330 of the light shielding layer 300. In otherwords, the spacer 500 overlaps the projection of the extending portion310 or the sub-extending portion 330 on the first substrate 100.

As indicated in FIG. 2, each spacer 500 comprises a main spacer 510 andan auxiliary spacer 520. The top side 511 of the main spacer 510 leanson the opposite substrate (the first substrate 100), but the top side521 of the auxiliary spacer 520 is separated from the opposite firstsubstrate 100 by a distance. The main spacer 510, which leans on theopposite substrate, is used as a main supporter between two substratesand may easily generate friction with the opposite substrate and causescratches. Therefore, the main spacer 510 must be disposed at a positioncorresponding to the extending portion 310 and overlaps the extendingportion 310 of the light shielding layer 300 in the normal direction ofthe first substrate 100 (the Z-axis). The extending portion 310 islarger than the main spacer 510, and can thus resolve the aestheticproblem caused by the main spacer 510. Relatively, the auxiliary spacer520 is disposed at a position corresponding to the extending portion 310(such as the second auxiliary spacer 520 counted from the right-handside of FIG. 2) or disposed at a position corresponding to thesub-extending portion 330 (other auxiliary spacers 520 of FIG. 2), suchthat the auxiliary spacer 520 overlaps the sub-extending portion 330 inthe normal direction of the first substrate 100 (the Z-axis).

It should be noted that the position of the main spacer 510 mustcorrespond to the extending portion 310. However, not each extendingportion 310 has a main spacer 510 corresponding thereto. That is, theauxiliary spacer 520 can also be disposed under the extending portion310.

In the embodiment indicated in FIG. 2, the main spacer 510 is differentform the auxiliary spacer 520 mainly in length. In some embodiments, themain spacer 510 can be different from the auxiliary spacer 520 mainly inwidth. For example, the width of the main spacer 510 is greater than thewidth of the auxiliary spacer 520. The present invention does not havespecific restrictions on the spacer.

FIG. 3 is a planar diagram of a display panel according to anotherembodiment of the invention. The display panel 2 of FIG. 3 is differentfrom the display panel 1 of FIG. 1 mainly in the position of theextending portion 310 of the light shielding layer 300. As indicated inFIG. 3, each pixel 20 comprises three sub-pixels R, G and B, and oneextending portion 310 only shields two pixels 20. The overlapping areabetween the pixel 20 located at the left half of the extending portion310 and the projection of the extending portion 310 is greater than theoverlapping area between the pixel 20 located at the right half of theextending portion 310 and the projection of the extending portion 310.Therefore, each pixel 20 located at the left half of the extendingportion 310 has lower aperture ratio and is defined as a first pixel 21.Each pixel 20 located at the right half of the extending portions 320(should be 310) but not shielded by the extending portion has largeraperture ratio and is defined as a second pixel 22.

FIG. 4 is a planar diagram of a display panel according to anotheralternate embodiment of the invention. The display panel 3 is differentfrom the display panel 1 of FIG. 1 mainly in the position of theextending portion 310 of the light shielding layer 300. As indicated inFIG. 4, one extending portion 310 only shields two pixels 20. Theoverlapping area between the pixel 20 located at the upper half of theextending portion 310 and the projection of the extending portion 310 isgreater than the overlapping area between the pixel 20 located at thelower half of the extending portion 310 and the projection of theextending portion 310. Therefore, each pixel 20 located at the upperhalf of the extending portion 310 has lower aperture ratio and isdefined as a first pixel 21, and each pixel 20 located at the lower halfof the extending portion 310 but not shielded by the extending portion310 has larger aperture ratio and is defined as a second pixel 22.

In some embodiments, it is possible that the projection of one extendingportion 310 is entirely projected on one pixel 20. Under suchcircumstance, each pixel overlapping the projection of the extendingportion on the first substrate is defined as a first pixel, and eachpixel not overlapping with the projection of the extending portion onthe first substrate is defined as a second pixel.

In above embodiments, the shape of the extending portion 310 or thesub-extending portion 330 of the light shielding layer 300 isexemplified by a circular shape. In some embodiments, the extendingportion 310 or the sub-extending portion 330 of the light shieldinglayer 300 can be an ellipse, a rectangle, a parallelogram or othershape. The extending portion 310 and the sub-extending portion 330 ofthe present invention can have any shapes as long as the area is largerthan each adjacent connecting portion and capable of shielding adjacentpixels.

In above embodiments, each pixel comprises three sub-pixels R, G and B.In some embodiments, each pixel may comprise four sub-pixels (such asRGBW) or more than four sub-pixels. The present invention does not havespecific restrictions on the number of sub-pixels.

Principles regarding the distribution of the extending portions 310 ofthe light shielding layer 300 of the present invention are explainedwith FIG. 5, a planar diagram of a plurality of display units 10 ofFIG. 1. Each display unit 10 comprises 12 pixels 20 arranged in a 6*2matrix (6 rows, 2 columns). A plurality of display units 10 are arrangedin a repetitive manner to form an image display region of the displaypanel 4. In FIG. 5, each pixel 20 is simplified and denoted by a square.The squared pixels 20 are further divided into first pixels 21 (denotedby slashed squares) and second pixels 22 (denoted by blank squares)according to the size of the area shielded by the extending portion 310or the sub-extending portion 320 (FIG. 1) of the light shielding layer300.

In each display unit 10 of FIG. 1 and FIGS. 2A and 2B, there is at mostone first pixel 21 per column and per row. In each display unit 10, allof the pixels 20 adjacent to the first pixel 21 are second pixels 22. Asindicated in FIG. 5, two adjacent pixels 20 refer to two pixels 20adjacent to each other by edge or corner. For example, the first pixel21 designated by “a” has eight adjacent pixels 20 designated by “b”,“c”, “d”, “e”, “f”, “g”, “h′ and “i.” All of the eight pixels 20 aresecond pixels 22. The first pixels 21 corresponding to a larger area ofthe light shielding layer are interlaced with the second pixels 22corresponding to a smaller area of the light shielding layer. Since suchpattern cannot be easily detected with human eyes, the viewer will notperceive any image strips.

As indicated in FIG. 5, the display unit 10 comprises 6*2 pixels 20arranged in a 6*3 matrix, m=6, n=2. Each display unit 10 at most has twofirst pixels 21. It is possible that each display unit 10 has only onefirst pixel 21.

Referring to FIG. 6, a planar diagram of a display panel according toanother embodiment of the invention is shown. In the display panel 5,each display unit 10 comprises 36 pixels 20 arranged in a 6*6 matrix (6rows, 6 columns), wherein m=n=6. In the entire image display region,each pixel 20 adjacent to the first pixel 21 is a second pixel 22. Ineach display unit 10, there is one first pixel 21 per column and perrow. For example, the first pixel 21 designated by “a” has eight pixels20 designated by “b”, “c”, “d”, “e”, “f”, “g”, “h” and “i” adjacentthereto, and all of the eight pixels 20 are second pixels 22 with higheraperture ratio.

Referring to FIG. 7, a planar diagram of a display panel according to analternate embodiment of the invention is shown. The display panel 6 ofFIG. 7 is different from the display panel 5 of FIG. 6 mainly in thateach display unit 10 of the display panel 6 does not necessarily haveone first pixel 21 per column and per row. As disclosed above, theposition of the first pixel 21 can be changed by adjusting the extendingportion 310 of the light shielding layer 300 (FIG. 2A). In the presentembodiment, after the display units 10 are arranged in a repetitivemanner, in the image display region, there will be one entire column orentire row whose pixels are merely second pixels 22, and image stripsgenerated due to the arrangement of the first pixel 21 can thus beimproved. For example, there is no first pixel 21 in the 4^(th) and the10^(th) rows (counted from the top) of the image display region of thedisplay panel 6 of FIG. 7

Referring to FIG. 8, a planar diagram of a display panel according to ofthe invention another alternate embodiment is shown. In the displaypanel 7, each display unit 10 comprises four pixels 20 arranged in a 2*2matrix (2 rows, 2 columns). Each display unit 10 has one first pixel 21.In the entire image display region, each pixel 20 adjacent to the firstpixel 21 is a second pixel 22. For example, the first pixel 21designated by “a” has eight pixels 20 designated by “b”, “c”, “d”, “e”,“f”, “g”, “h” and “”” adjacent thereto, and all of the eight pixels 20are second pixels 22. In the present embodiment, the first pixels 21 aredistributed with high density, and are capable of effectively reducingthe viewers' perception image strips even in a high PPI product.

It should be noted that pixel arrangement of the display panel of thepresent invention is not limited to the above exemplifications. Anyarrangements will do as long as the following criteria are satisfied:(1) In a display unit, there is at most one pixel with lower apertureratio (the first pixel) per column and per row. (2) In the entiredisplay panel, each pixel with lower aperture ratio (the first pixel) issurrounded by pixels with higher aperture ratio (the second pixels).Through such arrangement, the viewers' perception of image strips can bereduced without reducing the overall aperture ratio of the displaypanel.

Through specific arrangement of the light shielding layer and pixelsdisclosed above, the present invention is capable of maintaining theaperture ratio of the display panel, avoiding the perception of imagestrips, and improving display quality.

While the invention has been described by way of example and in terms ofthe preferred embodiment (s), it is to be understood that the inventionis not limited thereto. On the contrary, it is intended to cover variousmodifications and similar arrangements and procedures, and the scope ofthe appended claims therefore should be accorded the broadestinterpretation so as to encompass all such modifications and similararrangements and procedures.

What is claimed is:
 1. A display panel, comprising: a first substratecomprising a plurality of display units arranged in a matrix and formingan image display region, wherein the display units comprise m*n pixelsarranged in an m*n matrix, each pixel has at least three sub-pixels, mand n are positive integers, m≧2, and n≧2; a second substrate oppositeto the first substrate; and a light shielding layer located between thefirst substrate and the second substrate, wherein the light shieldinglayer comprises a plurality of extending portions, a projection of oneof the extending portions on the first substrate overlaps at least twoof the pixels, one of the two pixels having larger overlapping area withthe extending portions is a first pixel, the other one having smalleroverlapping area with or not overlapping the extending portions is asecond pixel, in each display unit, there is at most one first pixel percolumn and per row, and in the image display region, all of the pixelsadjacent to the first pixel are second pixels.
 2. The display panelaccording to claim 1, wherein the light shielding layer furthercomprises a plurality of connecting portions connecting the extendingportions and disposed between any two adjacent sub-pixels, and a widthof each connecting portion is smaller than a width of each extendingportion.
 3. The display panel according to claim 2, the light shieldinglayer further comprises a plurality of sub-extending portions, any twoadjacent sub-extending portions are connected by the connectingportions, and a width of each sub-extending portion is greater than awidth of each connecting portion, and a width of each sub-extendingportion is smaller than a width of each extending portion.
 4. Thedisplay panel according to claim 3, further comprising: a plurality ofmain spacer located between the first substrate and the second substrateand corresponding to the extending portions of the light shieldinglayer; and a plurality of auxiliary spacers located between the firstsubstrate and the second substrate and corresponding to the extendingportions or the sub-extending portions of the light shielding layer. 5.The display panel according to claim 4, wherein the main spacers and theauxiliary spacers are formed on one of the first substrate and thesecond substrate, and distance from a top side of each auxiliary spacerto the other one of the first substrate and the second substrate isgreater than distance from a top side of each main spacer to the otherone of the first substrate and the second substrate.
 6. The displaypanel according to claim 5, wherein, the light shielding layer, the mainspacers and the auxiliary spacers are disposed on the second substrate.7. The display panel according to claim 1, wherein in the image displayregion, there is at least one column whose pixels are all second pixels.8. The display panel according to claim 1, wherein in the image displayregion, there is at least one row whose pixels are all second pixels. 9.A display panel, comprising: a first substrate comprising a plurality ofdisplay units arranged in a matrix and forming an image display region,wherein the display units comprise m*n pixels arranged in an m*n matrix,each pixel has at least three sub-pixels, m and n are positive integers,m≧2, and n≧2; a second substrate opposite to the first substrate; and alight shielding layer located between the first substrate and the secondsubstrate, wherein the light shielding layer comprises a plurality ofextending portions, a projection of one of the extending portions on thefirst substrate overlaps one of the pixels, the pixel overlapping theprojection of the extending portion is a first pixel, other pixels notoverlapping the projection of each extending portion are second pixels,in each display unit, there is at most one first pixel per column andper row, and in the image display region, all of the pixels adjacent tothe first pixel are second pixels.
 10. The display panel according toclaim 9, wherein the light shielding layer further comprises a pluralityof connecting portions connecting the extending portions and disposedbetween any two adjacent sub-pixels, and a width of each connectingportion is smaller than a width of each extending portion.